Emotional Decision Making in Large Crowds Alexei Sharpanskykh 1 and Kashif Zia 2 1 Abstract Currently it is widely recognised that emotions of people influence their decisions. In this paper the role of emotions in social decision making in large technically assisted crowds is investigated. For this a formal, computational model is proposed, which integrates existing neurological and cognitive theories of affec- tive decision making. Based on this model several variants of a large scale crowd evacuation scenario were simulated. By analysis of the simulation results it was established that spread of emotions in a crowd increases resistance of agent groups to opinion changes and supports continuity of decision making in a group. 1 Introduction Currently it is widely recognised that emotions of people influence their decisions [1,3]. Previously human decision making has been considered as entirely rational and has been modelled using economic utility-based theories [7,8]. Purely rational decision making models were disapproved by many empirical studies (see e.g. [15]). However, devising a better alternative addressing the limitations of these models by combining cognitive and affective aspects still remains a big challenge. To address this challenge several computational models were proposed [4,13,14], which use variants of the OCC model developed by Ortony, Clore and Collins [11] as a basis. The OCC model postulates that emotions are valenced re- actions to events, agents, and objects, where valuations are based on similarities between achieved states and goal states. Thus, emotions in this model have a cog- nitive origin. In contrast to these approaches, we employ a neurological fundament comprising several theories, based on which a model of emotional decision mak- ing is built. All these theories were validated empirically. The theories comple- ment each other in the proposed model in a consistent manner by supplying each other with technical details used for refinement of abstract principles, as described in Section 2. In Social Science literature [9,10] empirical evidences exist indicating that emotions increase a group’s cohesion. In this paper we examine two hypotheses related to these findings by simulation based on the developed model: 1 1 VU University Amsterdam, De Boelelaan 1081a, Amsterdam, the Netherlands 2 Institute for Pervasive Computing, Johannes Kepler University, Linz, Austria